#include <stdio.h>
#include<math.h>
int IsPrime(int number) {
    if (!(number % 2) || number <= 1)
        return 0;
    for (int i = 2; i <= sqrt(number); i++) {
        if (!(number % i))
            return 0;
    }
    return number;
}

int main()
{
    int number;
    scanf("%d", &number);
    if (IsPrime(number)) printf("%d is prime number.\n", number);
    else printf("%d is not prime number.\n", number);
    return 0;
}